ref: 17ebe55031ae6945ad1f671b69267a672328e4b1
dir: /sys/src/cmd/hjfs/dump.c/
#include <u.h> #include <libc.h> #include <thread.h> #include "dat.h" #include "fns.h" int copydentry(Fs *fs, FLoc *a, Loc *b, char *nname) { Buf *ba, *bb, *bc; Dentry *d; int i, rc; FLoc c; if(!namevalid(nname)){ werrstr(Einval); return -1; } ba = getbuf(fs->d, a->blk, TDENTRY, 0); if(ba == nil) return -1; bb = getbuf(fs->d, b->blk, TDENTRY, 0); if(bb == nil){ putbuf(ba); return -1; } rc = newentry(fs, b, bb, nname, &c, 1); if(rc < 0){ err1: putbuf(bb); putbuf(ba); return -1; } bc = getbuf(fs->d, c.blk, TDENTRY, 0); if(bc == nil) goto err1; d = &bc->de[c.deind]; memcpy(d, &ba->de[a->deind], sizeof(*d)); strcpy(d->name, nname); for(i = 0; i < NDIRECT; i++) if(d->db[i] != 0) chref(fs, d->db[i], 1); for(i = 0; i < NINDIRECT; i++) if(d->ib[i] != 0) chref(fs, d->ib[i], 1); bc->op |= BDELWRI; putbuf(bc); putbuf(bb); putbuf(ba); return 0; } static void resetldumped(Fs *fs) { Loc *l; for(l = fs->rootloc->gnext; l != fs->rootloc; l = l->gnext) l->flags &= ~LDUMPED; } int fsdump(Fs *fs) { char buf[20], *p, *e; int n, rc; Tm *tm; Chan *ch, *chh; Buf *b; wlock(fs); tm = localtime(time(0)); snprint(buf, sizeof(buf), "%.4d", tm->year + 1900); ch = chanattach(fs, CHFNOLOCK|CHFDUMP); ch->uid = -1; if(ch == nil){ wunlock(fs); return -1; } if(chanwalk(ch, buf) < 0){ chh = chanclone(ch); rc = chancreat(chh, buf, DMDIR|0555, OREAD); chanclunk(chh); if(rc < 0) goto err; if(chanwalk(ch, buf) < 0) goto err; } b = getbuf(fs->d, ch->loc->blk, TDENTRY, 0); if(b == nil) goto err; for(n = 0; ; n++){ e = buf + sizeof(buf); p = seprint(buf, e, "%.2d%.2d", tm->mon + 1, tm->mday); if(n > 0) seprint(p, e, "%d", n); rc = findentry(fs, ch->loc, b, buf, nil, 1); if(rc < 0) goto err; if(rc == 0) break; } putbuf(b); rc = copydentry(fs, fs->rootloc, ch->loc, buf); chanclunk(ch); resetldumped(fs); wunlock(fs); return rc; err: chanclunk(ch); wunlock(fs); return -1; } static int willmodify1(Fs *fs, Loc *l) { Buf *p; Loc *m; uvlong i, r; Dentry *d; int rc; rc = chref(fs, l->blk, 0); if(rc < 0) return -1; if(rc == 0){ dprint("willmodify: block %lld has refcount 0\n", l->blk); werrstr("phase error -- willmodify"); return -1; } if(rc == 1) goto done; p = getbuf(fs->d, l->next->blk, TDENTRY, 0); if(p == nil) return -1; d = getdent(l->next, p); if(d != nil) for(i = 0; i < d->size; i++){ rc = getblk(fs, l->next, p, i, &r, GBREAD); if(rc <= 0) continue; if(r == l->blk) goto found; } phase: werrstr("willmodify -- phase error"); putbuf(p); return -1; found: rc = getblk(fs, l->next, p, i, &r, GBWRITE); if(rc < 0){ putbuf(p); return -1; } if(rc == 0) goto phase; putbuf(p); if(r != l->blk){ /* * block got dumped, update the loctree so locs * point to the new block. */ qlock(&fs->loctree); for(m = l->cnext; m != l; m = m->cnext) if(m->blk == l->blk) m->blk = r; l->blk = r; qunlock(&fs->loctree); } done: l->flags |= LDUMPED; return 0; } int willmodify(Fs *fs, Loc *l, int nolock) { Loc **st; int sti, rc; if((l->flags & LDUMPED) != 0) return 1; if(!nolock){ again: runlock(fs); wlock(fs); } st = emalloc(sizeof(Loc *)); *st = l; sti = 0; for(;;){ if((st[sti]->flags & LDUMPED) != 0 || st[sti]->next == nil) break; st = erealloc(st, (sti + 2) * sizeof(Loc *)); st[sti + 1] = st[sti]->next; sti++; } rc = 0; for(; sti >= 0; sti--){ rc = willmodify1(fs, st[sti]); if(rc < 0){ free(st); if(!nolock){ wunlock(fs); rlock(fs); } return -1; } } if(!nolock){ wunlock(fs); rlock(fs); if(chref(fs, l->blk, 0) != 1) goto again; } free(st); return rc; }